1. Field of the Invention
The present invention relates to a spin conduction element and a magnetic sensor and magnetic head which use spin conduction.
2. Description of the Related Art
There have been known various elements that detect external magnetic fields (for example, refer to Japanese Unexamined Patent Application Publication No. 2007-299467 below). Magnetic heads and magnetic sensors used in, for example, hard disk drives (HDD) and the like have been desired to detect magnetic fields from minute regions and have high output characteristics. Conventional tunnel magnetoresistance (TMR) devices have a spin-valve structure and have relatively high output characteristics. A method of making elements finer is employed for detecting magnetic fields from minute regions. However, making the elements finer increases element resistances. For example, a limit of improvement in characteristics begins to appear in areas with a recording density of 1 Tbit/inch or more, thereby requiring other structures and methods. A method proposed as a method for resolving this problem is to detect a magnetic field from a minute area with high sensitivity by detecting a component with spins rotated by an external magnetic field based on a spin-current conduction phenomenon referred to as the “Hanle effect” (for example, refer to Japanese Unexamined Patent Application Publication Nos. 2011-176012 and 2010-213913 below).